ad5380.c

  1// SPDX-License-Identifier: GPL-2.0-only
  2/*
  3 * Analog devices AD5380, AD5381, AD5382, AD5383, AD5390, AD5391, AD5392
  4 * multi-channel Digital to Analog Converters driver
  5 *
  6 * Copyright 2011 Analog Devices Inc.
  7 */
  8
  9#include <linux/device.h>
 10#include <linux/err.h>
 11#include <linux/i2c.h>
 12#include <linux/kernel.h>
 13#include <linux/module.h>
 14#include <linux/spi/spi.h>
 15#include <linux/slab.h>
 16#include <linux/sysfs.h>
 17#include <linux/regmap.h>
 18#include <linux/regulator/consumer.h>
 19
 20#include <linux/iio/iio.h>
 21#include <linux/iio/sysfs.h>
 22
 23#define AD5380_REG_DATA(x)	(((x) << 2) | 3)
 24#define AD5380_REG_OFFSET(x)	(((x) << 2) | 2)
 25#define AD5380_REG_GAIN(x)	(((x) << 2) | 1)
 26#define AD5380_REG_SF_PWR_DOWN	(8 << 2)
 27#define AD5380_REG_SF_PWR_UP	(9 << 2)
 28#define AD5380_REG_SF_CTRL	(12 << 2)
 29
 30#define AD5380_CTRL_PWR_DOWN_MODE_OFFSET	13
 31#define AD5380_CTRL_INT_VREF_2V5		BIT(12)
 32#define AD5380_CTRL_INT_VREF_EN			BIT(10)
 33
 34/**
 35 * struct ad5380_chip_info - chip specific information
 36 * @channel_template:	channel specification template
 37 * @num_channels:	number of channels
 38 * @int_vref:		internal vref in uV
 39 */
 40struct ad5380_chip_info {
 41	struct iio_chan_spec	channel_template;
 42	unsigned int		num_channels;
 43	unsigned int		int_vref;
 44};
 45
 46/**
 47 * struct ad5380_state - driver instance specific data
 48 * @regmap:		regmap instance used by the device
 49 * @chip_info:		chip model specific constants, available modes etc
 50 * @vref:		actual reference voltage used in uA
 51 * @pwr_down:		whether the chip is currently in power down mode
 52 * @lock:		lock to protect the data buffer during regmap ops
 53 */
 54struct ad5380_state {
 55	struct regmap			*regmap;
 56	const struct ad5380_chip_info	*chip_info;
 57	int				vref;
 58	bool				pwr_down;
 59	struct mutex			lock;
 60};
 61
 62enum ad5380_type {
 63	ID_AD5380_3,
 64	ID_AD5380_5,
 65	ID_AD5381_3,
 66	ID_AD5381_5,
 67	ID_AD5382_3,
 68	ID_AD5382_5,
 69	ID_AD5383_3,
 70	ID_AD5383_5,
 71	ID_AD5390_3,
 72	ID_AD5390_5,
 73	ID_AD5391_3,
 74	ID_AD5391_5,
 75	ID_AD5392_3,
 76	ID_AD5392_5,
 77};
 78
 79static ssize_t ad5380_read_dac_powerdown(struct iio_dev *indio_dev,
 80	uintptr_t private, const struct iio_chan_spec *chan, char *buf)
 81{
 82	struct ad5380_state *st = iio_priv(indio_dev);
 83
 84	return sysfs_emit(buf, "%d\n", st->pwr_down);
 85}
 86
 87static ssize_t ad5380_write_dac_powerdown(struct iio_dev *indio_dev,
 88	 uintptr_t private, const struct iio_chan_spec *chan, const char *buf,
 89	 size_t len)
 90{
 91	struct ad5380_state *st = iio_priv(indio_dev);
 92	bool pwr_down;
 93	int ret;
 94
 95	ret = kstrtobool(buf, &pwr_down);
 96	if (ret)
 97		return ret;
 98
 99	mutex_lock(&st->lock);
100
101	if (pwr_down)
102		ret = regmap_write(st->regmap, AD5380_REG_SF_PWR_DOWN, 0);
103	else
104		ret = regmap_write(st->regmap, AD5380_REG_SF_PWR_UP, 0);
105
106	st->pwr_down = pwr_down;
107
108	mutex_unlock(&st->lock);
109
110	return ret ? ret : len;
111}
112
113static const char * const ad5380_powerdown_modes[] = {
114	"100kohm_to_gnd",
115	"three_state",
116};
117
118static int ad5380_get_powerdown_mode(struct iio_dev *indio_dev,
119	const struct iio_chan_spec *chan)
120{
121	struct ad5380_state *st = iio_priv(indio_dev);
122	unsigned int mode;
123	int ret;
124
125	ret = regmap_read(st->regmap, AD5380_REG_SF_CTRL, &mode);
126	if (ret)
127		return ret;
128
129	mode = (mode >> AD5380_CTRL_PWR_DOWN_MODE_OFFSET) & 1;
130
131	return mode;
132}
133
134static int ad5380_set_powerdown_mode(struct iio_dev *indio_dev,
135	const struct iio_chan_spec *chan, unsigned int mode)
136{
137	struct ad5380_state *st = iio_priv(indio_dev);
138	int ret;
139
140	ret = regmap_update_bits(st->regmap, AD5380_REG_SF_CTRL,
141		1 << AD5380_CTRL_PWR_DOWN_MODE_OFFSET,
142		mode << AD5380_CTRL_PWR_DOWN_MODE_OFFSET);
143
144	return ret;
145}
146
147static const struct iio_enum ad5380_powerdown_mode_enum = {
148	.items = ad5380_powerdown_modes,
149	.num_items = ARRAY_SIZE(ad5380_powerdown_modes),
150	.get = ad5380_get_powerdown_mode,
151	.set = ad5380_set_powerdown_mode,
152};
153
154static unsigned int ad5380_info_to_reg(struct iio_chan_spec const *chan,
155	long info)
156{
157	switch (info) {
158	case IIO_CHAN_INFO_RAW:
159		return AD5380_REG_DATA(chan->address);
160	case IIO_CHAN_INFO_CALIBBIAS:
161		return AD5380_REG_OFFSET(chan->address);
162	case IIO_CHAN_INFO_CALIBSCALE:
163		return AD5380_REG_GAIN(chan->address);
164	default:
165		break;
166	}
167
168	return 0;
169}
170
171static int ad5380_write_raw(struct iio_dev *indio_dev,
172	struct iio_chan_spec const *chan, int val, int val2, long info)
173{
174	const unsigned int max_val = (1 << chan->scan_type.realbits);
175	struct ad5380_state *st = iio_priv(indio_dev);
176
177	switch (info) {
178	case IIO_CHAN_INFO_RAW:
179	case IIO_CHAN_INFO_CALIBSCALE:
180		if (val >= max_val || val < 0)
181			return -EINVAL;
182
183		return regmap_write(st->regmap,
184			ad5380_info_to_reg(chan, info),
185			val << chan->scan_type.shift);
186	case IIO_CHAN_INFO_CALIBBIAS:
187		val += (1 << chan->scan_type.realbits) / 2;
188		if (val >= max_val || val < 0)
189			return -EINVAL;
190
191		return regmap_write(st->regmap,
192			AD5380_REG_OFFSET(chan->address),
193			val << chan->scan_type.shift);
194	default:
195		break;
196	}
197	return -EINVAL;
198}
199
200static int ad5380_read_raw(struct iio_dev *indio_dev,
201	struct iio_chan_spec const *chan, int *val, int *val2, long info)
202{
203	struct ad5380_state *st = iio_priv(indio_dev);
204	int ret;
205
206	switch (info) {
207	case IIO_CHAN_INFO_RAW:
208	case IIO_CHAN_INFO_CALIBSCALE:
209		ret = regmap_read(st->regmap, ad5380_info_to_reg(chan, info),
210					val);
211		if (ret)
212			return ret;
213		*val >>= chan->scan_type.shift;
214		return IIO_VAL_INT;
215	case IIO_CHAN_INFO_CALIBBIAS:
216		ret = regmap_read(st->regmap, AD5380_REG_OFFSET(chan->address),
217					val);
218		if (ret)
219			return ret;
220		*val >>= chan->scan_type.shift;
221		*val -= (1 << chan->scan_type.realbits) / 2;
222		return IIO_VAL_INT;
223	case IIO_CHAN_INFO_SCALE:
224		*val = 2 * st->vref;
225		*val2 = chan->scan_type.realbits;
226		return IIO_VAL_FRACTIONAL_LOG2;
227	default:
228		break;
229	}
230
231	return -EINVAL;
232}
233
234static const struct iio_info ad5380_info = {
235	.read_raw = ad5380_read_raw,
236	.write_raw = ad5380_write_raw,
237};
238
239static const struct iio_chan_spec_ext_info ad5380_ext_info[] = {
240	{
241		.name = "powerdown",
242		.read = ad5380_read_dac_powerdown,
243		.write = ad5380_write_dac_powerdown,
244		.shared = IIO_SEPARATE,
245	},
246	IIO_ENUM("powerdown_mode", IIO_SHARED_BY_TYPE,
247		 &ad5380_powerdown_mode_enum),
248	IIO_ENUM_AVAILABLE("powerdown_mode", IIO_SHARED_BY_TYPE, &ad5380_powerdown_mode_enum),
249	{ }
250};
251
252#define AD5380_CHANNEL(_bits) {					\
253	.type = IIO_VOLTAGE,					\
254	.indexed = 1,						\
255	.output = 1,						\
256	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |		\
257		BIT(IIO_CHAN_INFO_CALIBSCALE) |			\
258		BIT(IIO_CHAN_INFO_CALIBBIAS),			\
259	.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE),	\
260	.scan_type = {						\
261		.sign = 'u',					\
262		.realbits = (_bits),				\
263		.storagebits =  16,				\
264		.shift = 14 - (_bits),				\
265	},							\
266	.ext_info = ad5380_ext_info,				\
267}
268
269static const struct ad5380_chip_info ad5380_chip_info_tbl[] = {
270	[ID_AD5380_3] = {
271		.channel_template = AD5380_CHANNEL(14),
272		.num_channels = 40,
273		.int_vref = 1250,
274	},
275	[ID_AD5380_5] = {
276		.channel_template = AD5380_CHANNEL(14),
277		.num_channels = 40,
278		.int_vref = 2500,
279	},
280	[ID_AD5381_3] = {
281		.channel_template = AD5380_CHANNEL(12),
282		.num_channels = 16,
283		.int_vref = 1250,
284	},
285	[ID_AD5381_5] = {
286		.channel_template = AD5380_CHANNEL(12),
287		.num_channels = 16,
288		.int_vref = 2500,
289	},
290	[ID_AD5382_3] = {
291		.channel_template = AD5380_CHANNEL(14),
292		.num_channels = 32,
293		.int_vref = 1250,
294	},
295	[ID_AD5382_5] = {
296		.channel_template = AD5380_CHANNEL(14),
297		.num_channels = 32,
298		.int_vref = 2500,
299	},
300	[ID_AD5383_3] = {
301		.channel_template = AD5380_CHANNEL(12),
302		.num_channels = 32,
303		.int_vref = 1250,
304	},
305	[ID_AD5383_5] = {
306		.channel_template = AD5380_CHANNEL(12),
307		.num_channels = 32,
308		.int_vref = 2500,
309	},
310	[ID_AD5390_3] = {
311		.channel_template = AD5380_CHANNEL(14),
312		.num_channels = 16,
313		.int_vref = 1250,
314	},
315	[ID_AD5390_5] = {
316		.channel_template = AD5380_CHANNEL(14),
317		.num_channels = 16,
318		.int_vref = 2500,
319	},
320	[ID_AD5391_3] = {
321		.channel_template = AD5380_CHANNEL(12),
322		.num_channels = 16,
323		.int_vref = 1250,
324	},
325	[ID_AD5391_5] = {
326		.channel_template = AD5380_CHANNEL(12),
327		.num_channels = 16,
328		.int_vref = 2500,
329	},
330	[ID_AD5392_3] = {
331		.channel_template = AD5380_CHANNEL(14),
332		.num_channels = 8,
333		.int_vref = 1250,
334	},
335	[ID_AD5392_5] = {
336		.channel_template = AD5380_CHANNEL(14),
337		.num_channels = 8,
338		.int_vref = 2500,
339	},
340};
341
342static int ad5380_alloc_channels(struct device *dev, struct iio_dev *indio_dev)
343{
344	struct ad5380_state *st = iio_priv(indio_dev);
345	struct iio_chan_spec *channels;
346	unsigned int i;
347
348	channels = devm_kcalloc(dev, st->chip_info->num_channels,
349				sizeof(struct iio_chan_spec), GFP_KERNEL);
350
351	if (!channels)
352		return -ENOMEM;
353
354	for (i = 0; i < st->chip_info->num_channels; ++i) {
355		channels[i] = st->chip_info->channel_template;
356		channels[i].channel = i;
357		channels[i].address = i;
358	}
359
360	indio_dev->channels = channels;
361
362	return 0;
363}
364
365static int ad5380_probe(struct device *dev, struct regmap *regmap,
366			enum ad5380_type type, const char *name)
367{
368	struct iio_dev *indio_dev;
369	struct ad5380_state *st;
370	unsigned int ctrl = 0;
371	int ret;
372
373	indio_dev = devm_iio_device_alloc(dev, sizeof(*st));
374	if (indio_dev == NULL)
375		return -ENOMEM;
376
377	st = iio_priv(indio_dev);
378
379	st->chip_info = &ad5380_chip_info_tbl[type];
380	st->regmap = regmap;
381
382	indio_dev->name = name;
383	indio_dev->info = &ad5380_info;
384	indio_dev->modes = INDIO_DIRECT_MODE;
385	indio_dev->num_channels = st->chip_info->num_channels;
386
387	mutex_init(&st->lock);
388
389	ret = ad5380_alloc_channels(dev, indio_dev);
390	if (ret)
391		return dev_err_probe(dev, ret, "Failed to allocate channel spec\n");
392
393	if (st->chip_info->int_vref == 2500)
394		ctrl |= AD5380_CTRL_INT_VREF_2V5;
395
396	ret = devm_regulator_get_enable_read_voltage(dev, "vref");
397	if (ret < 0 && ret != -ENODEV)
398		return dev_err_probe(dev, ret, "Failed to get vref voltage\n");
399	if (ret == -ENODEV) {
400		st->vref = st->chip_info->int_vref;
401		ctrl |= AD5380_CTRL_INT_VREF_EN;
402	} else {
403		st->vref = ret / 1000;
404	}
405
406	ret = regmap_write(st->regmap, AD5380_REG_SF_CTRL, ctrl);
407	if (ret)
408		return dev_err_probe(dev, ret, "Failed to write to device\n");
409
410	ret = devm_iio_device_register(dev, indio_dev);
411	if (ret)
412		return dev_err_probe(dev, ret, "Failed to register iio device\n");
413
414	return 0;
415}
416
417static bool ad5380_reg_false(struct device *dev, unsigned int reg)
418{
419	return false;
420}
421
422static const struct regmap_config ad5380_regmap_config = {
423	.reg_bits = 10,
424	.val_bits = 14,
425
426	.max_register = AD5380_REG_DATA(40),
427	.cache_type = REGCACHE_MAPLE,
428
429	.volatile_reg = ad5380_reg_false,
430	.readable_reg = ad5380_reg_false,
431};
432
433#if IS_ENABLED(CONFIG_SPI_MASTER)
434
435static int ad5380_spi_probe(struct spi_device *spi)
436{
437	const struct spi_device_id *id = spi_get_device_id(spi);
438	struct regmap *regmap;
439
440	regmap = devm_regmap_init_spi(spi, &ad5380_regmap_config);
441
442	if (IS_ERR(regmap))
443		return PTR_ERR(regmap);
444
445	return ad5380_probe(&spi->dev, regmap, id->driver_data, id->name);
446}
447
448static const struct spi_device_id ad5380_spi_ids[] = {
449	{ "ad5380-3", ID_AD5380_3 },
450	{ "ad5380-5", ID_AD5380_5 },
451	{ "ad5381-3", ID_AD5381_3 },
452	{ "ad5381-5", ID_AD5381_5 },
453	{ "ad5382-3", ID_AD5382_3 },
454	{ "ad5382-5", ID_AD5382_5 },
455	{ "ad5383-3", ID_AD5383_3 },
456	{ "ad5383-5", ID_AD5383_5 },
457	{ "ad5384-3", ID_AD5380_3 },
458	{ "ad5384-5", ID_AD5380_5 },
459	{ "ad5390-3", ID_AD5390_3 },
460	{ "ad5390-5", ID_AD5390_5 },
461	{ "ad5391-3", ID_AD5391_3 },
462	{ "ad5391-5", ID_AD5391_5 },
463	{ "ad5392-3", ID_AD5392_3 },
464	{ "ad5392-5", ID_AD5392_5 },
465	{ }
466};
467MODULE_DEVICE_TABLE(spi, ad5380_spi_ids);
468
469static struct spi_driver ad5380_spi_driver = {
470	.driver = {
471		   .name = "ad5380",
472	},
473	.probe = ad5380_spi_probe,
474	.id_table = ad5380_spi_ids,
475};
476
477static inline int ad5380_spi_register_driver(void)
478{
479	return spi_register_driver(&ad5380_spi_driver);
480}
481
482static inline void ad5380_spi_unregister_driver(void)
483{
484	spi_unregister_driver(&ad5380_spi_driver);
485}
486
487#else
488
489static inline int ad5380_spi_register_driver(void)
490{
491	return 0;
492}
493
494static inline void ad5380_spi_unregister_driver(void)
495{
496}
497
498#endif
499
500#if IS_ENABLED(CONFIG_I2C)
501
502static int ad5380_i2c_probe(struct i2c_client *i2c)
503{
504	const struct i2c_device_id *id = i2c_client_get_device_id(i2c);
505	struct regmap *regmap;
506
507	regmap = devm_regmap_init_i2c(i2c, &ad5380_regmap_config);
508
509	if (IS_ERR(regmap))
510		return PTR_ERR(regmap);
511
512	return ad5380_probe(&i2c->dev, regmap, id->driver_data, id->name);
513}
514
515static const struct i2c_device_id ad5380_i2c_ids[] = {
516	{ "ad5380-3", ID_AD5380_3 },
517	{ "ad5380-5", ID_AD5380_5 },
518	{ "ad5381-3", ID_AD5381_3 },
519	{ "ad5381-5", ID_AD5381_5 },
520	{ "ad5382-3", ID_AD5382_3 },
521	{ "ad5382-5", ID_AD5382_5 },
522	{ "ad5383-3", ID_AD5383_3 },
523	{ "ad5383-5", ID_AD5383_5 },
524	{ "ad5384-3", ID_AD5380_3 },
525	{ "ad5384-5", ID_AD5380_5 },
526	{ "ad5390-3", ID_AD5390_3 },
527	{ "ad5390-5", ID_AD5390_5 },
528	{ "ad5391-3", ID_AD5391_3 },
529	{ "ad5391-5", ID_AD5391_5 },
530	{ "ad5392-3", ID_AD5392_3 },
531	{ "ad5392-5", ID_AD5392_5 },
532	{ }
533};
534MODULE_DEVICE_TABLE(i2c, ad5380_i2c_ids);
535
536static struct i2c_driver ad5380_i2c_driver = {
537	.driver = {
538		   .name = "ad5380",
539	},
540	.probe = ad5380_i2c_probe,
541	.id_table = ad5380_i2c_ids,
542};
543
544static inline int ad5380_i2c_register_driver(void)
545{
546	return i2c_add_driver(&ad5380_i2c_driver);
547}
548
549static inline void ad5380_i2c_unregister_driver(void)
550{
551	i2c_del_driver(&ad5380_i2c_driver);
552}
553
554#else
555
556static inline int ad5380_i2c_register_driver(void)
557{
558	return 0;
559}
560
561static inline void ad5380_i2c_unregister_driver(void)
562{
563}
564
565#endif
566
567static int __init ad5380_spi_init(void)
568{
569	int ret;
570
571	ret = ad5380_spi_register_driver();
572	if (ret)
573		return ret;
574
575	ret = ad5380_i2c_register_driver();
576	if (ret) {
577		ad5380_spi_unregister_driver();
578		return ret;
579	}
580
581	return 0;
582}
583module_init(ad5380_spi_init);
584
585static void __exit ad5380_spi_exit(void)
586{
587	ad5380_i2c_unregister_driver();
588	ad5380_spi_unregister_driver();
589
590}
591module_exit(ad5380_spi_exit);
592
593MODULE_AUTHOR("Lars-Peter Clausen <lars@metafoo.de>");
594MODULE_DESCRIPTION("Analog Devices AD5380/81/82/83/84/90/91/92 DAC");
595MODULE_LICENSE("GPL v2");